| APA | HGSO. (2012, February 16). In Acronym Geek. Retrieved 08:47, February 16, 2012, from http://www.acronymgeek.com/HGSO |
| MLA | "HGSO." Acronym Geek. (2012). Acronym Geek. 16 Feb 2012 <http://www.acronymgeek.com/HGSO>. |
| MHRA | 'HGSO', Acronym Geek, 16 February 2012, <http://www.acronymgeek.com/HGSO> [accessed 16 February 2012] |
| Chicago | "HGSO", http://www.acronymgeek.com/HGSO (accessed February 16, 2012). |
| CBE/CSE | HGSO [Internet]. Acronym Geek; 2012 Feb 16 [cited 2012 Feb 16]. Available from: http://www.acronymgeek.com/HGSO. |
| Bluebook | HGSO, http://www.acronymgeek.com/HGSO (last visited February 16, 2012). |
| Bluebook: Harvard JOLT | See Acronym Geek, HGSO, http://www.acronymgeek.com/HGSO (optional description here) (as of Feb. 16, 2012, 08:47). |
| AMA | HGSO. Acronym Geek. February 16, 2012, 08:47. Available at: http://www.acronymgeek.com/HGSO. Accessed February 16, 2012, 08:47. |